ARDMS (American Registry for Diagnostic Medical Sonography) Practice Test

Which of the following represents the approximate diameter reduction of the internal carotid artery (ICA) when evaluating the spectral waveform and peak systolic velocity (PSV) and end-diastolic velocity information?

1. 25-49%

2. 50-79%

3. 80-99%

4. 100%

The correct answer is: 80-99%

The approximate diameter reduction of the internal carotid artery is represented by the spectral waveform and peak systolic velocity (PSV) and end-diastolic velocity information. Options A, B, and D are incorrect. These options represent a smaller percentage reduction in diameter of the internal carotid artery compared to option C. A 25-49% reduction would still allow for adequate blood flow, while a 100% reduction would result in complete blockage of the artery. Option C, representing an 80-99% reduction, is a more clinically significant and accurate representation of the diameter reduction of the internal carotid artery when evaluating spectral waveform and velocity information.